Honeycomb Cake (Banh Bo Nuong)

Fragrant and delicious this slightly chewy tapioca cake is infused with coconut milk and Pandan flavor. A word of caution: This is not the easiest cake to make. The success of this cake is in achieving the vertical striations which when cut across looks like a bee’s honeycomb and hence the name Honeycomb Cake. The ingredients and directions are very specific so please follow the recipe closely.

Notes on the Recipe, Tips and Tricks

Be sure to use single-acting baking powder instead of double-acting baking powder. (Single-acting works when wet. Double-acting works with moisture and heat.) Most of the baking powders available in the grocery stores (ex: Rumford, Royal, Calumet, etc.) are double-acting and will not work with this recipe. The cake rises nicely in the oven but once removed from the oven, it falls flat. (Sad!) For single-acting baking powder, I know of only two brands: Alsa and Dr. Oetker. The Alsa brand (sold as a packet of little pink envelopes) is what most people use and it’s only sold in the Asian grocery stores. If you can find the Alsa brand, this baking powder works just fine and you’ll want to use one entire envelope for the below recipe. I used Dr. Oetker’s because it’s sold in a store near me. Unfortunately, it did not give yield the beautiful honeycombs even though I read it’s a single-acting baking powder. Because finding single-acting baking powder can be a frustrating task, in this recipe we make our own using ingredients which are readily available in every grocery store.

Be prepared to make this cake a few times before you are successful, so buy a full tray of eggs and extra tapioca starch. The size of the eggs is important too. The recipe calls for extra large or jumbo eggs.

Make sure your baking soda is not expired. We all have a container in our cupboard and have no idea how long it’s been in there. Buy a fresh box for this recipe.

Once we add the baking powder we need to work quickly to get the cake into the oven.

I use a 9″ round springform pan. You can go a bit smaller if you want a thicker cake but don’t use anything larger than a 10″ pan.

Preheat oven to 325 degrees Fahrenheit and place a the springform baking pan in the oven.

In a small saucepan over low heat, add coconut milk, water and sugar. Stir until dissolved. Remove from heat and allow to cool.

In a medium bowl, sift together tapioca starch and rice flour. Set aside.

In a small bowl, combine the cream of tartar and baking soda to make the single-acting baking powder. Set aside.

In a large bowl, add eggs, oil, and vanilla extract. Pierce eggs yolks with a knife. Gently whisk everything together for about 1 minute. Do not introduce air in the egg mixture by whipping or beating the eggs.

Add coconut syrup to egg mixture and whisk together gently. Add 1/2 of the sifted flour mixture and mix together until mostly combined. Add the remaining flour mixture and continue whisking gently. The batter is lumpy at first but continue whisking slowly (approximately 2-3 minutes ) to dissolve the lumps. Add the pandan paste and blend well. There will be some small lumps in the batter still.

Add the single-acting baking powder and whisk until smooth, approximately 2 minutes. Note the batter becomes foamy as it reacts with the baking powder.

Remove the baking pan from the oven and spray it with a generous amount of non-stick cooking spray. Strain the batter into the baking pan. Use the whisk to work through any remaining lumps in the strainer.

Bake the cake for 30-35 minutes. Check for doneness by inserting a toothpick into the center. If the toothpick comes out clean, the cake is done. Remove from oven and allow to cool.

The cracks on top are typically due to too much heat or the cake being too close to the heating element. Reduce the heat a bit or move the cake farther away from the heating element. A lopsided cake is because of uneven heating in the oven. Rotate the cake halfway through baking and this should help. Good Luck!

Hi Kim, Sorry I missed this comment…I am so glad to hear you were successful with making Honeycomb Cake. It’s good to know you had to adjust your oven temperature. What makes this recipe a bit tricky is oven temperatures aren’t always precise and so adjustments may be needed. Thanks for stopping by to share your results!

Hi Trang, I followed your recipe word for word and my cake could not be any more perfect. I did however have to bake mine 10 minutes longer than your instruction, but the cake is simply perfect. Thank you.

Is it normal for the cake to fall flat when you take it out of the oven? My cakes never have that honeycomb texture. Is there any secret to it? Also, to confirm, you are using glutinous rice flour correct? I’ve never used that flour with it, and perhaps that’s why my cake turns out weird.

Hi Oanh, The cake should not fall flat when removed from the oven. That usually means the walls of the cake aren’t solid enough to support the weight of the cake. Try baking your cake for 10-15 minutes longer to make sure the walls are solid and this should help it not collapse. Please use rice flour and not glutinous rice flour. The rice flour is added to tone-down the chewiness of the tapioca starch. This is a tricky cake to make but don’t give it. Good Luck!

Hello Trang, mine’s also Trang. Made the cake using 9″ springform pan. I had my reservation about using a 2-piece pan since liquidy batter tends to leak through these pans. Did it anyway since you said you used one. Well, about 1/3 of the batter leaked through during baking (good thing I put the pan inside a baking pan) and I ended up with 2/3 of the cake in the springform pan and 1/3 on the bottom inside the baking pan. It did have some of the vertical striations, but not much. Cake was still good and soft.

I’ll be using a 1-piece pan next time. Any ideas how to incorporate fresh pandan juice into this cake? I’m thinking replacing the 1/4 c water with fresh-squeezed pandan juice in the first step.

Hi Trang, I would suggest using a regular cake pan if your springform pan leaks. The springform makes it easier to remove the cake but I’ve made the cake many times using a round and bundt cake pans. Yes, you can definitely replace the water with fresh pandan juice–it’ll be so fragrant! Good luck the next time around and please stop back to share your comments. 🙂

Hi I’m confused on the single acting baking powder. In your notes section it states I could use the alsa brand and use the whole packet for the recipe but in the ingredient section it says to use 1tbs. Could you clearify how must single acting baking powder I would use if I use the Alsa brand. Thanks

If you use the Alsa brand, you will use the whole packet. If you don’t have the Alsa brand, you will use my recipe to make 1 Tbsp of single-acting powder by combining 2 tsp cream of tartar + 1 tsp baking soda. I hope that clears it up. Let me know if you have more questions.

What kind of oven do you use? Top and bottom heat or fan based? I have tried to make this cake, but it failed unfortunately. I don’t see any reaction with the baking powder and my batter is really runny. But i’ll will try it again for sure! Thank you so much for your nice recipes!

Hi Syt, I am sorry to hear the cake didn’t turn out for you. If the baking powder didn’t react with the batter, it may not be fresh. Also the batter should not be runny but should have a consistency similar to what I showed in the video. Please double check the measurements or perhaps cut back on 1 egg. I use a conventional oven with heating elements on top and bottom of the oven. This is a tough cake to make successfully. Please don’t give it. It does take multiple tries. Good Luck and let me know if I can help.

Hi Nga, You don’t have to buy it. I show you how to make it in this recipe. 1 Tbsp single-acting baking powder = 2 tsp cream of tartar + 1 tsp baking soda (You can find these ingredients in all American grocery stores in the baking/spices section.) If you have a Viet grocery store, you can buy the brand Alsa (comes in a pink envelope, Google “alsa baking powder” for a picture). It’s single-acting baking powder and you can use that if it’s more convenient. Please follow the directions closely. The technique is important and the recipe can be tricky. Good Luck and let me know if you have any questions!

Hi, I'm Trang and welcome to RunAwayRice! I'm a recipe developer, home cook, food stylist and blogger with a passion for healthy eating and simple cooking. I take traditional Vietnamese dishes and give them a modern twist! More about me...

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